因式分解:1.1+a^2-9b^2-2a2.2ax^2-6ax-8a解方程:(a^2-4)(a/a+2-1/a-2-1)(a^2-4)[(a)/(a+2)-(1)/(a-2)-1]

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因式分解:1.1+a^2-9b^2-2a
2.2ax^2-6ax-8a
解方程:(a^2-4)(a/a+2-1/a-2-1)
(a^2-4)[(a)/(a+2)-(1)/(a-2)-1]

(1)1+a^2-9b^2-2a=a^2-2a+1-9b^2
=(a-1)^2-(3b)^2
=(a-1+3b)(a-1-3b)
(2)
2ax^2-6ax-8a
=2a(ax^2-3x-4)
=2a(x+1)(x-4)
(3)
(a^2-4)[a/(a+2)-1/(a-2)-1]
=(a+2)(a-2)[a/(a+2)-1/(a-2)-1]
=a(a-2)-(a+2)-(a+2)(a-2)
=a^2-2a-a-2-(a^2-4)
= -3a+2

1 + a" - 9b" - 2a
= a" - 2a + 1 - 9b"
= (a - 1)" - (3b)"
= (a - 1 + 3b)(a - 1 - 3b)

2ax" - 6ax - 8a
= 2a(x" - 3x - 4)
= 2a(x" - 4x + x - 4)
= 2a[ (x - 4)x + (x - 4) ...

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1 + a" - 9b" - 2a
= a" - 2a + 1 - 9b"
= (a - 1)" - (3b)"
= (a - 1 + 3b)(a - 1 - 3b)

2ax" - 6ax - 8a
= 2a(x" - 3x - 4)
= 2a(x" - 4x + x - 4)
= 2a[ (x - 4)x + (x - 4) ]
= 2a(x - 4)(x + 1)

(a" - 4)[ a/(a + 2) - 1/(a - 2) - 1 ]
= a(a + 2)(a - 2)/(a + 2) - (a + 2)(a - 2)/(a - 2) - (a" - 4)
= a(a - 2) - (a + 2) - a" + 4
= a" - 2a - a - 2 - a" + 4
= 4 - 2 - 2a - a - a" + a"
= 2 - 3a

收起

1、
1+a^2-9b^2-2a
=(1-2a+a²)-9b²
=(1-a)²-(3b)²
=(1-a+3b)(1-a-3b)
2、
2ax^2-6ax-8a
=2a(x²-3x-4)
=2a(x+1)(x-4)
3、
(a^2-4)(a/a+2-1/a-2-1)
=(a+2)(a-2)[a/(a+2)-1/(a-2)-1]
=(a+2)(a-2)(a²-2a-a-2-a²+4)/(a+2)(a-2)
=-3a+2